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-   -   P0743 Code Question (http://www.wranglerforum.com/f210/p0743-code-question-242817.html)

gp90 05-15-2013 12:58 PM

P0743 Code Question
 
Recently bought a '97 tj 4.0 32rh, 35's w 4:88's..... I'm getting a P0743 code but the trans seems to be shifting fine (three sp but sounds like a 4sp). I checked the fuse and getting power to both sides. But when I checked the wiring on the trans the orange/lt gr wire has no voltage. I spot checked it up to the firewall fiquring I'd find a broke wire didn't find anything. I ohm'd it and the reading was .576. I've read some posts that only one wire is powered and some say both are powered. Does the org/lt gr wire have continuous voltage? Or is the converter staying locked up. :banghead: RPM's are @ 2750 at 60-65 mph. Any info would be appreciated

RUBI 4 MY MRS 05-15-2013 02:45 PM

The red/light green wire has power from fuse 11 in the fuse block. The orange/light green is controlled through the PCM. I think it is grounded when the PCM wants the converter locked up. If the rd/lg has power to the trans then you have to unplug the connector to check the or/lg. That one goes to the C-3, b11 pin at the PCM. That is at one corner of the white connector. See if you have continuity between that pin & the connector end at the trans & make sure the pin connection at the PCM is good (no corrosion etc.). After that it is either the wiring inside the trans or the PCM. If you feel the 4th gear (converter locking up) then it sounds like it is working. Have you tried resetting the CEL to see if the code returns?

gp90 05-15-2013 03:22 PM

I reset it yesterday, drives good shifts every time but still getting a code. i'll unplug the connector at the trans and PCM and check that. Thanks

gp90 05-26-2013 05:30 PM

Pulled the connector and wire checked out good. No voltage on pin 11. Checked voltage with key in the on position. Any suggestions for my next option?

RUBI 4 MY MRS 05-27-2013 12:38 AM

You misread my instructions. There should not be power at pin 11. There should be power (key on) at the red/light green wire from fuse 11. Then there should be continuity in the orange/light green wire between the connector at the trans & pin 11 at the PCM connector. I’m reading this code as though there must be an open condition since it is not blowing a fuse I would eliminate a shorted condition. There is also the connection where it passes through the trans housing, that might be bad. Still with an open circuit I wouldn’t think it would be locking up at all.


Since there is a solenoid that operates the clutch I would guess that there should be resistance (don't know the value) between the 2 terminals at the trans connector. Check that & make sure it is not open (no continuity) there.


Since you seem sure it is locking up (feels like 4th gear), does it act like it is unlocking when you let off the throttle or does it try to bog down as it comes to idle?

Be sure the connector at the PCM is good at pin 11 as noted above.

It is also possible the PCM could be bad.(?)

From the FSM: P0743 -- Torque Converter Clutch Solenoid CKT -- An open or shorted condition detected in the torque converter part throttle unlock solenoid control circuit (3 speed auto RH trans. only).

gp90 05-27-2013 08:11 PM

It has bogged down a time or two right at idle but normally shifts good. The pins and connector seem to be good. I'll check between the 2 terminals next. Thanks again


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